Means for preventing clogging of air conveyers



Feb. 11, 1930. w. EVANS ,7

MEANS FQR PREVENTING CLOGGING OF AIR CONVEYERS Filed 001;. '7, 1927Patented Feb. 11, 1930 UNITED STATES PATENT orric WILSON EVANS, orcIIIcAGo, ILLINOIS, Assienon, BY ,MESNE Assreimnnrs, 'ro NATIONALALUMINATE CORPORATION, or CHICAGO, ILLmoIs, A oonronAr oN or DELAWAREMEANS FOR PREVENTING CLOGGING OF AIR CONITEYERS Application filedOctober 7, 1927. Serial No. 224,595.

My invention relates to improvements in process and means for preventingclogging of air conveyers and has for one object to provide meanswhereby an intermittently operated conveying mechanism handlinghydroscopic material may be protected against clogging and obstruction.

Experience shows that in handling such material as sodium aluminate forwater softening, table salt or other hydroscopic materials by the use ofa blower or fan which conveys a dust laden column of air, that when theapparatus is shut down for any considerable period of time,if there arechanges in temperature or changes in the moisture con tent of the air,there is likely to be a deposit of the hydroscopic moistened material inthe A fan and in the conveying passages resulting from moistening ofthematerial by water of condensation and the like.

In order to prevent this, I propose to provide means whereby the fan andthe discharge system will all be constantly kept at such a temperatureas will prevent the formation of water of condensation and therebymaintain a condition of dryness such that those particles of thehydroscopic material which may be left in the system when the systemgoes out of operation will not be permitted to absorb water andtherefore not permitted to deposit or adhere to the surfaces.

I propose to do this by providing as an integral part of the fan a ringtype electric heater which will surround the air intake of the fan andheat the air to some extent as it rushes in. This heater willhave acontinuous heating eifect. and will be in operation constantly but itbecomes more importantwhen the plant is shut down because it is duringshut down periods that deposition and cloggingtakes place. Since the fanis located at the lower end of the discharge pipe, the electric heaterwhich will keep the fan and fan chamber warm will cause convectioncurrents of air, the heated air from the fan chamber passing up throughthe discharge pipe and heating it and thus maintaining the parts at alltimes in a condition such that no moisture will be formed and thereforeno clogging take place.

through a conveyer A and spout A to a fan A The fan is driven by a motorA and discharges dust and air drawn in through the funnel A upwardlythrough the conveyer pipe A The conveyer pipe A discharges into the topof a watertreatment tank B, water coming into the tank through the pipeB the water and air conveyed solid material passing down through thestand pipe to the bottom of the tank B the treated water passing outthrough the overflow pipe B In the fan housing is a propeller fan C.Arranged about the intake opening to the fan and between the center ofrotation of the fan and the wall of the housing is an electric coilheater C This heater may be of any suitable type. It is preferably builtinto the fan housing itself and as shown extends throughout a large partof the fan chamber and surrounds the intake portion of the fan so thatthe air as it passes into the fan is heated by this electric heater.Since the electric heater is in constant operation whether the fan isrunning or not, the fan chamber and the air in it is always kept warm.Since the air intake to the fan chamber is never closed, this warm aircanrise through the pipe A and be replaced constantly by cold surroundinthe intake opening the fan chamber being located in the low point of theSystem.

Signed at Chicago, coilnty of Cook, and 5 State of Illinois, this 5thday of October,

WILSON EVANS.

